We must know something about the original context of a biblical book to interpret it properly, and understanding the historical context of 1 Corinthians is particularly helpful for understanding this epistle. The city of Corinth, capital of the province of Achaia, was one of the most important cities in the first-century Roman Empire. Located on a narrow isthmus that connected the Peloponnese to the rest of Greece, Corinth was a point of entry into Europe for those traveling from the east. Sailors would transport goods overland through the city from one port to another instead of going around the Peloponnesian peninsula by ship because it enabled them to avoid hazardous sailing conditions. All kinds of people came to the city to benefit from its commercial significance, bringing with them their various religions, philosophies, ethnicities, and more. As such, Corinth was a major city that featured all the benefits and drawbacks one might expect from an important metropolis. One commentator calls it the New York, Los Angeles, and Las Vegas of the ancient world all rolled into one. If you could succeed in Corinth, you could succeed anywhere. So, multitudes of people, with all their virtues and vices, flocked to the city for the prospect of economic gain.
Because of Corinth’s strategic location for reaching many different people from around the world, it is little wonder that Paul planted a church in the city, spending eighteen months there sometime between AD 49 and 52 (Acts 18:1–18). First Corinthians is actually the second letter Paul sent to Corinth after leaving the city, as 1 Corinthians 5:9–10 references a letter Paul sent to that church before writing 1 Corinthians. In turn, 1 Corinthians is written in response to a letter sent to Paul from the Corinthian believers (see 1 Cor. 7:1), where they asked the Apostle to take up several matters and questions.
As we will see in our study of 1 Corinthians, the common sins in Corinth made their way into the church. Thus, it is remarkable that Paul, in today’s passage, writes that the Christians there were “sanctified in Christ Jesus” (1 Cor. 1:2). The fundamental reality for believers, even in our sin, is that we have been set apart as holy unto God in Christ. Having been set apart as holy, we are then called to be holy in practice. We do not make ourselves holy but must live out the holy identity that we possess in Christ.